1. Field of the Invention
The present invention relates to an apparatus for adjusting spacing between endless or crawler tracks of a working vehicle having a backhoe implement or the like.
2. Description of the Prior Art
A conventional working vehicle having right and left crawler tracks is disclosed in Japanese Patent Publication Kokai No. 5-331877, for example. These crawler tracks are movable by the same amount toward and away from the longitudinal centerline of the working vehicle. In this type of working vehicle, both of the crawler tracks are moved toward the centerline even when it is desired to move only one of the crawler tracks toward the centerline.
Where, for example, a backhoe, which is one type of working implement, is used to dig earth adjacent a wall, the swivel deck should be placed as close to the wall as possible to dig earth adjacent the wall. Thus, a digging operation is started after the working vehicle is placed parallel and close to the wall in order to move the swivel deck as close to the wall as possible.
However, with the above conventional construction, an operation to vary the spacing between the right and left crawler tracks causes both of the crawler tracks to move by the same amount relative to the centerline. When the crawler track opposed to the wall is moved toward the centerline, the caterpillar track remote from the wall will also be moved by the same amount toward the centerline.
As a result, the spacing between the right and left crawler tracks will become small. In some cases, a better balance is desired when the swivel deck is turned to direct the backhoe implement to a truck or the like parked in a position opposite the wall across the working vehicle, to load the truck with earth.